This invention relates to controller systems for pools and spas.
Electronic control systems have been employed to control various functions. Typically, however, the power hookups for the different components associated with the pool or spa have been run directly through circuit breakers in a main or auxiliary panel to the various components, such as the pump, heater and lights. This is a time consuming task, and one which can lead to wiring mistakes, in view of the number of wiring connections which need to be made. There is therefore a need to simplify the power hookups to the various components, in order to control costs and provide more reliable installations.
A problem with pools is maintaining the level of water within the pool. Evaporation losses can be significant, and so it is advantageous to have an automated system for keeping the water level at a given desired level. Stand alone systems for doing this are known, but tend to be somewhat complex. It would be advantageous to integrate such a system with the pool controller, for reliability, ease of installation and cost savings.
Emergency shutoff switches are typically mounted close to the spa, to enable quick shutoff of pumps and other functions in an emergency. It would be an advantage to provide an electrical shutoff switch which did not require high power connections to the switch, and whose installation could be verified by the controller.
Ground fault circuit interruption devices are typically employed in pool and spa controls. It would be an advantage to provide a technique for testing for proper operation and installation of these circuits.
The pool plumbing system typically includes a filter system for removing particulates from the pool or spa water. These commonly use diatomaceous earth or other filtering agents. As the filter becomes filled with particulates removed from the water, the filter back pressure rises, and ultimately for proper operation the filter must be cleaned, e.g. by backflushing the filter. Presently, a sight pressure gauge is mounted on the filter, so that the pool maintenance technician can visually check the back pressure status. It would improve the maintenance of the filter operation to automate the pressure reading.
The water circulation system for the pool/spa also includes a heater for warming the pool and/or spa water for the user""s comfort. This heater is typically gas-operated, and does not operate properly when the gas pressure is too low. It would therefore improve the reliability and operation of the water circulation system if a technique could be found to monitor the gas pressure and provide a message and/or control signals in the event of a low gas pressure condition.
Power loads imposed by the pool system""s electrical components can be considerable. Techniques for efficiently using the power load rating of the control system are therefore needed.
A control system for a pool and spa installation is described, which provides for a simplified installation with effective ground fault protection. Main line voltage service for the pool and spa equipment is provided through a single line voltage service and a single ground fault circuit interrupter (GFCI) device. The control system acts as a distribution system for controlling the pool and spa equipment, with a circuit board assembly including individual circuit protection devices and switching circuits. Because the primary line voltage supply is through a single GFCI, testing of proper ground fault operation is facilitated through a ground fault test. Moreover, the installation costs of the control system are substantially reduced over those of conventional pool controller systems, because many of the wiring connections are made on the circuit board assembly.
The controller system is housed in a metal cabinet with a main bay in which all line voltage wiring is routed, and a plurality of secondary bays isolated from the main bay, through which low voltage wiring is routed from the main bay. The controller system includes a printed circuit board assembly which is configured for ready removal and replacement from the cabinet without the need for disconnecting the line voltage conductors from a set of pressure connectors attaching the connectors to a terminal block. The controller system is configured for field wiring.
A power management improvement is provided, wherein the line voltage service to the controller system is a line service, e.g. 240 VAC, and two line voltage 120 VAC loads are powered, one from a first circuit connected between a first line voltage phase conductor at 120 VAC and a neutral conductor, the other from a second circuit connected between a second line voltage phase conductor at 120 VAC and the neutral conductor. The two line voltage loads can be lighting circuits in an exemplary embodiments.
In accordance with another aspect of the invention, a test algorithm is implemented with the controller system, wherein the control system is prevented from normal operation if the GFCI test fails to indicate that the GFCI is operating properly.
Another aspect of the invention is an automated pool filling facility, wherein the pool owner manually enters a fill command through the controller panel, and the controller system automatically opens the fill valve for a predetermined time interval, and subsequently automatically closes the fill valve when the time interval elapses. Thus, the owner need only provide the initial instruction to add water to the pool, and does not have to remember to close the valve some time later.
An intelligent emergency disconnect switch system can be included with the controller system. The switch system is mounted near the pool or spa area, for ready access in the event of an emergency situation in which the line voltage loads such as the water pump should be shut down immediately. The switch system is connected by low voltage wiring to the controller system cabinet. The controller system senses the closure of the emergency switch and opens the switches or relays providing line voltage to the line voltage loads controlled by the system. Closure of the emergency switch also remotely induces a ground fault, which will result in tripping the GFCI, and interrupting line voltage supply to the controller system. Thus, the emergency switch system has redundant line voltage interrupt facilities. The emergency switch system also includes a sensing circuit feature through which the controller system can sense the presence of the emergency switch system. The controller system can issue a warning message or prevent normal operation of the pool and spa system if the controller system detects that the emergence switch system is not connected.
In accordance with another aspect of the invention, the pool and spa service system includes a gas pressure sensor mounted in the natural gas line running to the water heater. The sensor provides gas pressure signals which are monitored by the controller system. If the gas pressure is below a threshold pressure, e.g. a minimum pressure for reliable heater operation, the system will shut down the heater, and provide a warning message on the control panel display. The service system also includes water pressure sensing to monitor the filter backpressure, and provide a warning message on the control panel display in the event the backpressure indicates that the filter needs service.
Another aspect of the invention is in an improved temperature sensor for sensing air or water temperature. Parallel variable resistance elements such as thermistors are incorporated in a common housing to provide separate temperature sensing circuits which can be read by the system controller. The use of multiple sensing circuits provides redundancy, and provides two temperature readings which are monitored by the controller.
Other features and advantages are described.